package com.trilead.ssh2.channel;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;

/**
 * A StreamForwarder forwards data between two given streams. If two
 * StreamForwarder threads are used (one for each direction) then one can be
 * configured to shutdown the underlying channel/socket if both threads have
 * finished forwarding (EOF).
 * 
 * @author Christian Plattner, plattner@trilead.com
 * @version $Id: StreamForwarder.java,v 1.1 2007/10/15 12:49:56 cplattne Exp $
 */
public class StreamForwarder extends Thread {
	OutputStream os;
	InputStream is;
	byte[] buffer = new byte[Channel.CHANNEL_BUFFER_SIZE];
	Channel c;
	StreamForwarder sibling;
	Socket s;
	String mode;

	StreamForwarder(Channel c, StreamForwarder sibling, Socket s,
			InputStream is, OutputStream os, String mode) throws IOException {
		this.is = is;
		this.os = os;
		this.mode = mode;
		this.c = c;
		this.sibling = sibling;
		this.s = s;
	}

	@Override
	public void run() {
		try {
			while (true) {
				int len = is.read(buffer);
				if (len <= 0)
					break;
				os.write(buffer, 0, len);
				os.flush();
			}
		} catch (IOException ignore) {
			try {
				c.cm.closeChannel(c,
						"Closed due to exception in StreamForwarder (" + mode
								+ "): " + ignore.getMessage(), true);
			} catch (IOException e) {
			}
		} finally {
			try {
				os.close();
			} catch (IOException e1) {
			}
			try {
				is.close();
			} catch (IOException e2) {
			}

			if (sibling != null) {
				while (sibling.isAlive()) {
					try {
						sibling.join();
					} catch (InterruptedException e) {
					}
				}

				try {
					c.cm.closeChannel(c, "StreamForwarder (" + mode
							+ ") is cleaning up the connection", true);
				} catch (IOException e3) {
				}

				try {
					if (s != null)
						s.close();
				} catch (IOException e1) {
				}
			}
		}
	}
}